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Area Codes

Listings
Directory of U.S. area codes and international country calling codes.
http://www.1areacodescountrycodes.com/
directory of U.S. area codes by state plus cities within each area code. Also lists Canadian area codes by province or territory.
http://www.allareacodes.com/
search by area code, state abbreviation, or city name.
http://www.areacodes.org/
features code lists, maps, and news to help you keep up with all the changes.
http://www.areacode-info.com/
Area code lookup with maps by state or by code.
http://www.areacodesearchengine.com/
zip code and area code lookup and conversion database.
http://www.jcsm.com/
Information about North American area codes, featuring changes and historical data.
http://www.lincmad.com/
information about the original area codes from 1947, their evolution to the current state, and future developments including area code splits and overlays. Also features area code maps.
http://www.LincMad.com/
Neutral, third party administrator that works with the telecommunications industry in developing area code relief plans.
http://www.nanpa.com/
features government links for each state.
http://www.stateabbreviations.us/